Quick answer
Aid is help — foreign aid, first aid — and also the verb, to aid. An aide is a person who assists someone, typically an official or politician. The E makes it a person, borrowed from French.
The core difference
Help itself, and a person who provides it.
- aid — assistance, or to assist: humanitarian aid, aid the investigation.
- aide — an assistant: a senior aide, a nurse's aide.
The hyphenated forms
Aide-de-camp is a military officer assisting a senior commander, and is where the E comes from — French. A hearing aid takes no E, because it is a device rather than a person. That is the reliable test: people take the E.
The common slip
"A political aid" describes assistance to a party rather than a person working for one. It is a small error but it reaches print regularly.
Frequently asked questions
Which spelling is a person?
Aide, with the E — from French.
Is it hearing aid or hearing aide?
Hearing aid — it is a device, not a person.
What is an aide-de-camp?
A military officer serving as assistant to a senior commander — the French phrase the E comes from.
